In its conference call with investors and U.S. Securities and Exchange Commission documents released Wednesday, the Waterbury-based company said its net sales were $1.3 billion for a 13-week period ending Dec. 29, up from a $1.158 billion quarter the previous year.

“Our strong first-quarter performance underscores the connection consumers have to their Keurig brewers; the soundness of our business model; and the value inherent in our brand portfolio,” said Brian P. Kelley, GMCR’s president and CEO, in a statement.

Single-serve portion packets made up the bulk of sales, amounting to $863.7 million worth of product, a 21 percent increase from the same period the previous year. Sales of brewers and accessories totaled $377.3 million, an increase of 14 percent. Other products and royalties decreased by 12 percent to $98.1 million.

The number of brewers sold was 4.95 million, an increase of 18 percent over the prior year period, but that amount doesn’t include returns.

Kelley, a former Coca-Cola executive who started at the end of last year, noted the untapped potential of the Keurig brand in the U.S. and globally. The new leadership came as the company announced earlier that year it formed an international business unit.

“We are in the early days of a marked evolution in how consumers purchase, prepare and customize hot beverages in their homes,” Kelley said. “With a robust innovation pipeline and a growing awareness and commitment to the Keurig brand, GMCR is well positioned to continue to lead this disruptive shift in consumer behavior.”